Bollstabruk, ten kilometres north of Kramfors, was one of the original iron mills of the Ådalen valley, founded in 1739. The surviving mill house, manor, and old workers' cottages line the river and give a clear picture of how a 19th-century company town in northern Sweden looked.
The site is small and walkable, with information boards in Swedish and English. It is more interesting if you have read a little about the industrial history of Norrland — the iron, then the pulp and timber, then the sudden collapse of all three in the 20th century.